1. Field of the Invention
This invention relates to a shock absorbing device for a bicycle, more particularly to a shock absorbing device which includes a damping member with a damping capacity that can be varied in response to a braking action of the bicycle.
2. Description of the Related Art
In order to lessen the shock as a result of unevenness of the road surface and transmitted to a handlebar of a bicycle, the conventional bicycle is generally provided with a shock absorbing device. The shock absorbing device includes a mount and a leg member which are respectively mounted to a support frame and a wheel axle and which are movable relative to each other in an upright direction, and a damping member which is disposed between the mount and the leg member to provide a damping action for the shock. However, when the handlebar is abruptly pressed by the combined inertial momenta of the mass of the rider and the mass of the bicycle as a result of a braking action, the mount will be moved abruptly downwardly and forwardly, thereby exposing the rider to danger.
The object of the present invention is to provide a shock absorbing device for a bicycle, which can decrease the damping capacity of a damping member thereof in response to a braking action so as to counteract the downward and forward movement of a handlebar, thereby enhancing safety and comfort.
According to this invention, the shock absorbing device includes a mount with a periphery. The mount is adapted to be mounted to the support frame, and has a confronting wall which faces downwards in an upright direction. A leg member includes a lower end which is adapted to be anchored to a wheel axle, and an intermediate segment which extends from the lower end in the upright direction and which terminates at an upper end that is spaced apart from the confronting wall and that is movable relative to the confronting wall in the upright direction. A driven member has an actuated portion which is disposed on the mount, and which is rotatable relative to the mount about a twisting axis in the upright direction, and a coupling portion which extends from the actuated portion in the upright direction and downwardly of the confronting wall. A twist actuating member is disposed in synchronized operation with the brake actuating member to twist the actuated portion of the driven member to rotate about the twisting axis so as to angularly move the coupling portion from a first position to a second position. A damping member is provided with a damping capacity, and is disposed between the upper end of the leg member and the confronting wall so as to diminish progressively the shock energy generated, by an abrupt movement of the upper end relative to the confronting wall, which is brought about by a sudden depression on the support frame by the combined inertial momenta of the mass of a rider and the mass of the bicycle when the brake actuating member is actuated, or by a shock transmitted upwards through the wheel axle as a result of unevenness of a road surface being traversed by the bicycle. A regulating member is configured to vary the damping capacity of the damping member in response to the angular movement of the coupling portion from the first position to the second position.